It is said that 70 to 80 percentage of the end-user response time is spent on the front-end. A major portion of this time is exhausted on downloading all the external components in a web page including, stylesheet, images, scripts, flash etc. An extra HTTP request adds 200+ milliseconds to a page (worldwide average). Since most of today’s browsers limit about 3 or 4 parallel requests at a time, a page with so many external references can cause the requests to get queued up. This may eventually cause the page loading time to increase. In short, the fewer files the web browser has to fetch that much faster the site loads. It’s as simple as that.
What is CSS sprite?
CSS sprites can be termed as a method for reducing the number of image requests to a web page by combining multiple images into a single image, and display the desired segment using CSS background-image and background-position properites. Now that almost all major browsers started supporting CSS background-image and background-position properties, CSS sprites are getting more significance.
Here I am presenting a cool overlapped pure CSS menu created using CSS sprites. This is an initial draft version, so far I have checked it only in Firefox 5.0, IE 9, Chrome 5.1 & Opera 11.0 and it looks fine. If anyone of you finds any issues in any other browsers, please let me know. Cool sprites is a pack of four different versions of the same menu.
CSS:
Code
.navi1 {
display:block;
height:72px;
margin:0 auto;
position:relative;
width:525px; }
.navi1 ul {
float:none;
list-style-image:none;
list-style-type:none;
margin:3px 0; }
.navi1 ul li {
background-image:url(tab-1.png);
background-repeat:no-repeat;
float:left;
height:72px;
margin:0px;
padding-top:5px;
position:absolute; }
.navi1 ul li a {
display:block;
height:100%;
width:100%; }
.navi1 ul li.sm1 {
background-position:0 0;
left:0px;
width:125px; }
.navi1 ul li.sm2 {
background-position:-125px 0;
left:100px;
width:124px; }
.navi1 ul li.sm3 {
background-position:-249px 0;
left:200px;
width:124px; }
.navi1 ul li.sm4 {
background-position:-373px 0;
left:300px;
width:125px; }
.navi1 ul li.sm5 {
background-position:-498px 0;
left:400px;
width:126px; }
.navi1 ul li:hover {
z-index:1000; }
.navi1 ul li.sm1:hover {
background-position:0 -75px; }
.navi1 ul li.sm2:hover {
background-position:-125px -75px; }
.navi1 ul li.sm3:hover {
background-position:-249px -75px; }
.navi1 ul li.sm4:hover {
background-position:-373px -75px; }
.navi1 ul li.sm5:hover {
background-position:-498px -75px; }
HTML:
Code
<div class="navi1">
<ul>
<li class="sm1"><a href="#"></a></li>
<li class="sm2"><a href="#"></a></li>
<li class="sm3"><a href="#"></a></li>
<li class="sm4"><a href="#"></a></li>
<li class="sm5"><a href="#"></a></li>
</ul>
</div>
